BEIJING, June 23 -- A record-breaking scale of more than 3,500 buildings and organizations in Hong Kong switched their indoor lights off for two hours Sunday night to combat light pollution and climate change through the biggest star-gazing in the history of the city.

"Dim It Brighten Up" was organized by Friends of the Earth and The International Year of Astronomy 2009 Hong Kong League, aimed to arouse people's awareness about environmental protection.

The city began to go into darkness at 8:00 p.m. when neon lights and electric lights in buildings across Hong Kong started to go out.

Hong Kong's skyline buildings including the International Finance Center and Hong Kong Convention and Exhibition Center joined more than 3,500 buildings around the Victoria Harbor to disseminate the message about light pollution, green gas emissions and climate change.

SOUNDBITE: Lam Chiu-ying, chairman of the Hong Kong Meteorological Society "The more lights we turn on, the more electricity we would consume, and the more carbon dioxide we would emit. Climate change has a significant impact on the future of human beings. We present our caring for the climate through this lights-off campaign. Today we have made the first step."

According to Lam, about 30,000 to 50,000 Hong Kong residents and tourists observed the night sky through up to 100 telescopes placed along the Avenue of Stars, turning the promenade into the biggest star-gazing station in the city.

Over 1,100 buildings and organizations have also signed an agreement with Friends of the Earth, pledging to switch off outdoor lights no later than midnight from Sunday night to save energy as a good earth neighbor.